Process of producing beta-gamma-dimethylerythrene.



Uniroas a rare FRITZ HOFMANN, KONRAD DELBR'U'CK, AND KURT MEISENBURG, OFELBERFELD, GERMANY, ASSIGNORS TO FARBE'NFABRIKEN VORM. FRIEDR. BAYER &00., OF ELBERFELD, GERMANY, A CORPORATION OF GERMANY.

PROCESS OF PRODUCING BETA-GAMMA-DIMETHYLERYTHRENE.

No Drawing.

Specification of Letters Patent.

Application filed May 9, 1912. Serial No. 696,160.

Patented Aug. 5,1913.

the German Empire, residing at Elberfeld,

Germany, have invented new and useful Improvements in Processes ofProducing Beta-Gamma-Dimethylerythrene, of which the following is aspecification.

Our invention concerns a new and valuable process which results in anexcellent yield of beta s gamma dimethylerythrene and which consists inheating pinacone with a. small quantity of sulfuric acid or a sulfonicacid. The use of a small amountof acid (less than the amount of pinaconereacted upon) results in much larger vields of the hydrocarbon than hasbeen obtained by processes heretofore known.

With a fraction of a per cent. only of the acid, and even with a fewthousandths of a per cent. of the acid, unusually large yields areobtained.

The process proceeds according to the following equation:

naphthalene 1.5-disulfonic acid, etc., can be used.

The acid thus used in small amounts acts probably as a catalytic ordehydrating acid.

We claim 1. The process-of producing an erythrene hydrocarbon whichcomprises distilling a pinacone with a small percentage of a dehydrating acid, and then separating the crythrene hydrocarbon,substantially as described.

2. The process of producing an erythrene hydrocarbon which comprisesdistilling a pinacone with a fraction of a per cent. of a dehydratingacid.

3. The process of producing an erythrene hydrocarbon which comprisesdistilling a pinacone with a fraction of a per cent. of sulfuric acid.

4. The process of producing an er threne hydrocarbon which comprisesdisti ling a pinacone with about oneone-hundredth of one per cent. ofdilute sulfuric acid.

5. The process of producing beta-gammadimethylerythrene which comprisesfirstdistilling pinacone with a small percentage of sulfuric acid andthen separating the beta gamma dimethylerythrene, substantially asdescribed.

6. The process of producing beta-gammadimethylerythrene which processcomprises first distilling pinacone with about one one-hundredth of oneper cent. of dilute sulfuric acid and then separating thebetagamma-dimethylerythrene, substantially as described.

In testimony whereof we have hereunto set our hands in the presence oftwo subscribing witnes'ses.

FRITZ HOFMANN. [L.s.]

Witnesses:

Harms NUFER, A. Norm.

